At age 74, Joe Biden has announced formation of a new political action committee called American Possibilities. He say it's a call to reawaken the nation's track record of "ordinary people doing extraordinary things," including finding a cure for cancer, a cause to which he dedicated his life after the death of his son Beau during his second term as vice president.

Inevitably, the announcement triggered new speculation that he might make a third try for the Oval Office, in spite of his age. (He would be America's most elderly president if elected in 2020.)

At a Democratic function in Las Vegas in late April, he replied to a question about another run: "Could I? Yes. Would I? Probably not."

In 2016, Mr. Biden seriously weighed seeking the Democratic nomination again, but a number of factors beyond his age, including his depression after Beau's death and candidate Hillary Clinton's wide lead in the polls and fund-raising, persuaded him to stand aside. Instead he campaigned vigorously for Ms. Clinton and other party candidates, particularly among blue-collar workers, a personal constituency.

Toward the end of the 2016 campaign, during which many such working-class stiffs, especially in the Rust Belt, flocked to Donald Trump, Mr. Biden spoke regretfully of the Democrats' failure to make a much stronger pitch to this old traditional party base. With his new PAC, he can be expected to work to recapture the House majority as a brake on Mr. Trump's legislative agenda.

With his party currently bereft of any obvious 2020 presidential candidate, it would be most understanding that Biden, still beloved in Democratic ranks (including by retired President Obama, who has rated him the nation's greatest vice president), would make one more try. No other Democrat can match his credentials with 36 years in the Senate and eight years as presidential understudy and as master campaigner.

Despite his 74 years, Mr. Biden has been a durable figure, having soldiered through the deaths of his first wife and infant daughter and later two brain aneurysms that nearly killed him. Perhaps his greater setbacks have been political at the hands of Republican foes, who over the years have relentlessly mocked and demonized him as garrulous windbag prone to self-inflicted damage. Yet in his state of Delaware he never lost an election over 44 years.

Outsiders, though, whether they like Mr. Biden or not, have never seemed to tire of quoting Bidenisms, including using the ultimate profanity picked up by microphones in describing to Obama his enactment of health-care reform in their first term as a "big f-----g deal."

Within Delaware, however, Joe Biden's trademark loquaciousness is widely dismissed almost as loveable excess. When local voters across the state were repeatedly asked about it during his vice-presidential campaigns, the frequent reply with a grin was simply, "That's Joe." Often, when he would make one promise or another to them, he would say, "I give you my word as a Biden," which Delawareans took to mean they could take it to the bank. Whether true or not, it was a great chip for a politician to be able to play, at least at home.

For all that, however, it seems unlikely at this juncture that Joe Biden, he of the winning smile and shoeshine, will take on another presidential campaign in his own behalf in 2020. He seems more motivated to rescue American politics from its current ugliness.

Rather, he prefers to cite America's past achievements: "We're the people who built the Hoover Dam and the Transcontinental Railroad, landed a man on the moon, cured polio, built the Internet and sequenced the human genome. And, yes, soon we will be the people who will find a cure for cancer."

"Thinking big is steeped into the DNA of the American soul," he said in announcing his American Possibilities PAC. "That's why the negativity, the pettiness, the small-mindedness of our politics drives me crazy."

And so he will stay in the political game as long as his health and commitment to his party allows, and who knows what that might bring?

Jules Witcover is a syndicated columnist and former long-time writer for The Baltimore Sun. His latest book is "The American Vice Presidency: From Irrelevance to Power" (Smithsonian Books). His email is juleswitcover@comcast.net.